Adjustable scaffold.



A. C. DAVIS.

ADJUSTABLE SGAFFOLD. APPLICATION FILED 13.15.0.26,1913.

M; 3L 1,824., Papentea septj29, 1914.

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GIE* lllllllll@ Aff/7W 6. Daf/f5 INVENTOR ATTORNEY A. O. DAVIS.

ADJUSTABLE SGAFFOLD.

l i APPLCATION .FILED DEG.2G,1913.

u.. )i 1L L ggm Patented Sept. 29, 1914.

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BNVENTOF with the .inner Wallof the stack, -soxthat the' l meeting'edgesfby .theyplates 7, which 'plates 8 4are bolted =to .one rim section of each .pair

'to simplify-.and perfect vthe .construction ofj the scaffolding itselfiandithe .means-for Ead` J STAT-nsf PATENT OFFIQE,

ARTHUR c.--DAv1s,'.-oF BIRMINGHAM,ALABAMA.'

.mms'rABLmsFFoLn LiSPecication ofIietters-'Patent 'Patented-2 Sept.f29,11914.

Application iiled Decembelfi26'f1913. SeriatNo; 808,792.

justing it in the stack.

A further object of `my invention -todesign the scaffolding so thatfit'.isslightlycom cave, haring 'its center, which supports .theI crane, raised above .and so .connected to the outer stack engaging rim member,zthat"the Weight of the crane Iandother parts -on ithe raised center of the-scaffold serves to expand and wedge therim ymember intoengagement greater the weight on the .sca}fl'old, `.the more securely it is held lin position.

A further object of my invention `is 'to eperfeet a novel means for 'raising and lowering' the scafl'oldinof to adjust it in the stack, the several4 ropes 'leading to the scaffold 'raising tackle being preferably' spliced together and led to the hoisting drum.

A further object 'of my invention is ,to improve the manner of connecting the vgoose-lA neck pole to the scaffold so that -it can'ber swung around freely without interfering-` with the hoisting cable which in my con.' struction `is not required to be 'passed through the pole.

My invention involves other novel -details of construction and arrangements of parts which are hereinafter more particularly described and' claimed, reference being had to the accompanying drawings, in w'hichz Figure 1 Ais a vertical sectional elevation through a standpipe showing the scaffolding and stack' in vertical cross section and, for the sake of clearness, also showing the frame, by which theA scaffold is supported' when moved and its hoisting tackle partly in elevation and partly in section. Fig; .2 is a top plan. view of Fig. l" with the pole shown in cross section. Figs. 3 and 4 show partial planand .elevation views, respectively, of a part of the sectional grip rim.

@edge of'the rim and the Figs. 5 and 6 are enlarged detail views show- 'f .ing an elevation and :a .ve rtical sectional -vieW'through the griprim. 'F.ig. 7 is ade- :ta'iliplan v1eW ofthe frame forsupporting member ofthe frame-shown infFig. l7.` Fig. --9-.1sa'crosssectional view of the pole ltaken onthe line -of Fig. 1. Fig. 10 :isa deftall view lof `the connection sleeve :for jointl .-1 togfetherasections f of :the zpole.

imiar referenceznumerals -refer -to simiila-r'p'arts throughout :the ldra-Wings.

'haveshown `my invention in-use 1n con- "thescal'oldwvhen 'being raised or lowered. k60 F1g."8 .isa detail elevation off the -end cross `nectionvv'i th a circular stack zcomprising 70 sections land l2, but it can obviously be adapted for use `with stacks having. other ycrosssectional shapes.

'The scaffold pro-per comprises an annular peripheral 'grip'rim Lvformed of angle' iron in 7 arcuate :sections 3, 4, :f5 and 6, each of `which sections .is preferably a quadrant. The sections 4'and y5 and the sections-3 and `(Sbeing connected" together in 4pairs .at their aand either bolted or riveted -to the other rim section of a pair. The meeting of vthe sections 5 6 and 3 4 lare :provided with plates 8 which are bolted to the -top "flanges g of the sections so as rto overhang the inner have opposing vertical flanges' 9 near tieir inner ledges which are provided with threaded alining openings to receive a screw -10 'which-.is re- 90 versely vthreaded at its ends and provided With a lnut 11 at its center bymeans of .which it can be turned in either direction to draw the'plates together or toforce them y apart, thereby expanding and contracting-9 the rim. lAs will be seen by reference to Fig. 6, this rim has-the outer face of its sections roughened by providing sharp out' standing spurs '12, which will increase' its 'grip against the inner Wall of the stack and 1 will alsov assist in preventing any tendency of the scaffold to creep during operations. I attach at intervals to the rim'pairs of radially disposed connecting bars which at their outer ends engage the top and bottom 1 face of the top 'flange of the rimand are fastened thereto by a bolt 1G. Thcse'bars connect the rim to an inverted dish sha-pcd central platform 13. Each air of connectingbarscomprise an upper at bar 14 and a 1 lower angle bar 15. The bars of each. pair engage the inclined outer edge of the platfform 13 on both sidesand are connected thereto by a bolt 17 which passes through an elongated slot 18- provided in the inclined outer edge of the platform 13. Wedges 19 are insert-ed at the inner ends of the `slots 18 and bear against the inner ends of each pair `of bars 14, 15. These bars are spaced apart, there'being preferably two pairs for each rim section andthey forma skeleton frame adapted to support any suitable ltype of fiooring (not shown). I bolt to the under face of the platform 13, and concentric therewith, a flanged collar 20 having its fianged portion connected by countersunk rivets to the plate 13. The depending ,collar portion is circular in cross section and has a vertically disposed round opening therethrough concentric with a central opening in the platform 1 3. I clamp about this eollar a sup} orting frame for the scaffold when.

being adjusted which comprises two similar reversely disposed bent metal bars which are provided with curved central portions 21 adapted to be vfitted about the collar and to be clamped thereto by the-bolts 22. The other ends 9.3 of these bars engage the fiange of the collar 20 and the outer edge of the platform 13 froinwhichfpoint they are inclined downwardly and bent apart from each other as shown more'clearly in Fig. 7."

To the Aouter ends of the bars I connect plates 24 which have attached to their centers vertical eyes 25. These eyes, as shown in Fig. 1, are disposed between radial pairs of bars 111, 15 so that a block and tackle 26 may be connected with each of them by a hook 27 and suspended by a hook 2S from an S-'hook )9 that engages the ltop ring of the stack. The ropes 30, leading from the two blocks and tackles-are spliced at 31 to a rope which extends down Athrough the stack to the hoisting machinery (not shown);

The goose-neck p ole 33 has its lower end fitted ,over and supported by a Vertical pin 34 which is connected to or' formed intergral with a horizontally swinging plate 35, which.

is pivoted, 'at its inner end, by a down turned cylindrical vtubular bearing 36 thatl fits into and turns in the alining opening in the platform 13 and collar 20. A series of sheave Wheels 37 are suitably connected -by clamps'38 to the pole, the wheel on the ver-v tical part of the pole being disposed with their inner peripheries'in alinement with the Central openingin the bearing 36'. A clamp 38 near thevupper en'd of the pole basa rearwardli/-extending hig; 39 perforated to ref ceiye a'i'ing 40'. .To this'ring 10 I connect" two o r more 'guy' ropes 41 which spread apart and haveconnected to their lower ends hooks 42-tliat engage in the boltiioles in the 4topsectiont2-'of the stack. These guy ropes Afserve efeetively'to brace the pole.- The es outer sheave wheelg'is pivote-d in the biturting ends of the pole sections.

cated end of the pole and a hoisting'cable 43 is passed up throufh the. center of platform '13- and about the wllieels 37 and carries atits end the ordinary hook 44. The weight of the pole can be adjusted by the provision of ari-intermediate section 45 which is shown connected above and below toV the up er and lower sections of the pole by means o cla-mp sleeves 46 which are bolted about the abutf In operation, it will be notedthat thepole 33 1s free to swing with the pivoted plate 35 aboutthe bearing 36 as a center so as to act on all sides of the staelt and, as it is turned,

the guyropes 41 are adjusted about the stack' to properly brace it. After fastening the hooks 27 and 29 of each block and Atackle to the top of the stack at one side and to an eye 25 of .the supporting frame,- the hoisting en gine can be used to adjust the scaffold vertically to ,the'desired'poin the bars Q3 engaging under and Supporting the platform 13, and thereupon the screws J are turned to spread the rim sections into firm engagement with the inner wall of the stark. The bolts 17 are loosened to permit the rim sections to move outwardlyv from the platform 13 and after the vrim in'engagement with the stack, the wedges 19 are driven into the slots 18 and the bolts 17 tightened. Thereafter the pull on the block and tacliles'by rope 32 -can be released and as the weight of the pole and scaffold, the pull of the hoisting cable, comes on the central dish-shaped platform 13 the latter tends to give down and in doing'so acts with a toggle action', through the pairs connecting plates 1-1, 15, to wedge with greater tightness and security the outer rim against the stack. This wedging action makes the scaffold the tighter as the weight on it increases. ln order to again adjust the platform the reverse operation takes lace.

signed that it can be taken apart in the stack and readily removed through the manhole in the bottom.

lVithout limiting myself to the speculedeta-ils of construction herembefore pointed It will be noted that the scaffold is so deslight upward inclination from the rim to means to adjustably connect the platform,

and

said radial connections` to the platform,

a. hoisting mechanism supported on --salid' platform, substantially as described.

2. In an adyustable scaffold, an expansible sectional rim, radial connections adgustably connecting said rim to acentral platform; 'a

eentralplatform. normally supported by .sa i d connections above the rim,'a hoisting'appa;

mms; mmmte. or.. sai@ cema plaoym, zm mans fm ocli Said, rim and pamm in space@ ramionshp, Said radial connections 'being t9 sans@ the weight of the c-enmi platfrm fo forca h@ rim. against th@ suz'oundng sinac as the phmm is plie down? subsiantally as described.

25. 'n'zm :Lcjusinabe Scafoj fi. Tim section adapted to the inner wall of a smak, Cent paform, hoisting mechanism sup- @d on said platform, mdaly disposed makers ajusmby cmmecng 'he p'iafolm mlm sections, a supimrng frame which xmstcd i10- zhe platform and projects bfejmnd Q-uezw point djmfn nd mvke :adjw bl@ conn ad@ e scaffold cnmp'isiflg a sl i rim, mums to expand said rim a; le s'aek, a, cential platform Spaed fwn f wimj maly spcsed ndine con and?, of sind 'hmm' 60mm-ations, and I mi in verose almmem. with the Camiel@ of me opening; in the 'pw bemwg of Said memgrr., a hea which jpasss up t? mugh opening: smid pla'urm m men'xb@ n.152 m Said shame *"res :L Trimg megsjn Work comme@ mg said azorm and rim, ami means to fors@ the xm cmp En@ inner Wall of the stack, substantay as dream-ibm.

1 1n :m adjustable scaod, :am m'evted dsvshaped center patfmm having a fiat centia top', a member' givfsd uente? of the* patezm and 351m to swim mrunta plane? they@ bail 4 ing extending axaly @Tf1 @mid uw through iis pive und .5a-id paorm, a, img pole mounzd in th@ fr@ and member, sheave Wheels connected to @le l and o, hoisting caba guided thfoug mi@ Upenl'lgs amd over whee mf m53 t0 bram ith@ upper @n of said @me 'i, :me adapted it@ detachaby engag@ the @mug and am expansbe rim sefzm'; conm( '15 and wila-pwd fw suppori; said pat'omr: L Stack, Substmtay as desabd.

wardy incline. peripheral in whclu. :me mdaly filaposed sois) :aw-:armi infamy 

